How does my 512kbps connection goes as high as 2.4Mbps?! Incredible!

hi people!
i am really confused with my internet connection!
i do lotsa video editing, and i share it with my friend.
the file sizes are quite large, usually around 300MB.
anyway, i have subscribed, to a broadband internet service provider.
it was the cheapest that was available here in Malaysia at that time.
it's a 512kbps connection and it was wonderful at the beginning, i could download and upload files up to 80kBytes sometimes! until, after 2 months, the company told me your usage is too much and you are hogging the bandwidth!!
well, i told them i'll be careful next time.
i don't know what happened, but the download speed just dropped!! i can now get only up to 12kBytes max!! anyway, the broadband company doesn't explain to me much, so i though i could ask you guys.
however, the upload speed is wonderful!! i used to send 1 file through the FTP, at it could get up to 10kB only...but now i've learnt i can send many files at the same time! so, i split the files into smaller chunks, and send like 50 files at the same time!! and it works just wonderfully!! i get total upload speeds of 300 kB!!! that is around 2.4Mbps!! it's unbelievable!
i wanted to know how this works!?!?
the company had told me that i could do this, that is i can get higher speeds than 512kbps...but, why is it just the upload?? why not the download?? i would really appreciate your feedback guys!! cuz i am looking for alternatives..
i donno if i can get the same 2.4Mbps!! on a DSL as well??
by the way, this broadband is shared...that is the company's excuse for the sudden drop in the connection speed...but i don't think that is it...cuz it was much better before and it all happened in a day, after they told me i am using too much bandwidth!!
and...you see i have gotten greedy over the fact that i can jump over the 512kbps...and i like to know, if i change to a dedicated connection, would it be the same??
please put me out of this confusion!! sorry for the LONG STORY of mine! hehe!
thanks in advance!

Let me get this straight....

You had a connection rated at 512 down and were getting 2.4 meg down, and they called you and yelled at you for using to much bandwidth.

Call them back, and tell them that this is out of your control, that they are total morons who have no business running an ISP, and that you know a certain senior member from this forum who, for a measly $60,000 a year show them how to properly limit bandwidth to their customers.

hahaha!
they really should...they don't know what they are talking about really...
by the way, that was the upload speed...
i once got 100 kilobytes of download speed as well! but that was an accident i suppose!!

now my download speed is awefully slow!
does it mean that they have really limited the bandwidth?? or it's just that other people are hogging it? (it's a shared service)
also...am i using othe people's resources, when i upload?? does it affect other people's download speed?? or are they separate?

If you are on a shared resource, then everything you do WILL affect them and everything they do WILL effect you. It's painfully obvious that the poor guys no nothing about bandwidth limitation and sharing.

But don't take it to heart. ALL internet connections are a shared resource, they only thing that changes is at what point in the route they become shared.

How does my 512kbps connection goes as high as 2.4Mbps?!

Simple:

If you purchase 512kbps plan from your ISP, then they have to guarantee that speed.

If there is bandwith available above that, and it is not tied up, most likely you will benefit.

That sounds like what happend at first. Until they capped your bandwith. Maybe you should close your account and open it under a different name?